a)Also at: The Pearlstone Center for Aeronautical Engineering Studies, Department of Mechanical Engineering, Ben-Gurion University of the Negev, Beersheva 84105, Israel, and at School of Natural Sciences and School of Engineering, University of California, Merced, CA 95344, author to whom correspondence should be addressed; electronic mail: jeff@bgu.ac.il

Abstract

We report the observation of a photovoltaiceffect with pronounced hysteresis. The phenomenon derives from the sharp transition in the dominant mode of electron transport in the tunnel diodes that regulate multijunction solar cells, and is only observable at high flux. These results emerged from measurements of cell current-voltage characteristics performed with miniature fiber-optic solar concentrators that can deliver flux levels up to 10 000 times that of ambient sunlight in a highly localized fashion. The ramifications of our findings for photovoltaic design, diagnostics, and performance are addressed, and a nondestructive determination of the peak and valley threshold current densities of tunnel diodes is presented.

Received 07 October 2004Accepted 14 December 2004Published online 10 February 2005

Acknowledgments:

We thank Vladimir Melnichak for technical assistance, and Gary Conley and Steve Horne of the Corp., Saratoga, CA for their support. One author (E. A. K.) thanks the Israel Ministry of Immigrant Absorption and the Daichmann Foundation for financial support.